Code reservation enabled PAPR reduction of digital CDM based channel aggregation for mobile fronthaul

Area of Science:

• Telecommunications Engineering
• Optical Communications
• Signal Processing

Background:

• Mobile fronthaul networks require efficient channel aggregation techniques.
• High peak-to-average power ratio (PAPR) in aggregated signals limits performance.
• Directly modulated lasers (DMLs) are sensitive to signal power variations.

Purpose of the Study:

• To propose and evaluate a code reservation technique for reducing PAPR in CDM-based channel aggregation.
• To investigate the impact of PAPR reduction on optical modulation index (OMI) and OSNR.
• To experimentally verify the transmission performance improvements in a mobile fronthaul scenario.

Main Methods:

• Numerical investigation of PAPR versus the number of aggregated channels in CDM.
• Experimental verification of a code reservation technique for PAPR reduction.
• Transmission of aggregated Long Term Evolution (LTE) signals over 10km standard single mode fiber (SSMF).

Main Results:

• The code reservation technique significantly reduced the PAPR of an aggregated signal (48x20MHz LTE, 64-QAM).
• PAPR reduction allowed for a larger OMI within the linear operation region of the DML.
• Optical signal-to-noise ratio (OSNR) improvement was observed.
• Receiver sensitivity improved by 4dB after 10km SSMF transmission.

Conclusions:

• The proposed code reservation technique is effective in mitigating PAPR for CDM-based mobile fronthaul.
• PAPR reduction enhances system performance by improving OSNR and receiver sensitivity.
• This technique offers a viable solution for advanced mobile fronthaul systems.